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Describe in detail what you know about the enthalpy, entropy, and free energy changes when a sample of gas condenses to a liquid. How does temperature affect these changes?.

User Makky
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When a gas condenses to liquid the process is exothermic with the release energy and the enthalpy change is negative. As liquid has more ordered structure than gas, the entropy, which is the measure of disorder decreases or ∆ S has a negative value.

Free energy is given by the Gibb's free energy equation,

∆G = ∆H –T∆S

For a process to be spontaneous ∆ G must be negative.

∆H is negative and ∆S is negative, so the magnitude of |T∆S| should be less than the magnitude of |∆H| in that way ∆G is always negative.

|T∆S| should be less than the magnitude of |∆H|, so to favor that T should be low. The process is spontaneous at a lower temperature than at a higher temperature.

User Sandeep Pathak
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